@article{NUMA_1978__31_132569,
     author = {R. Schultz},
     title = {Ein {Abstiegsverfahren} f\"ur {Approximationsaufgaben} in normierten {R\"aumen.}},
     journal = {Numerische Mathematik},
     pages = {77--96},
     year = {1978},
     volume = {31},
     zbl = {0413.65010},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1978__31_132569/}
}